Nirmal Purja is a Nepal-born naturalised British mountaineer. Prior to taking on a career in mountaineering, he served in the British Army with the Brigade of Gurkhas followed by the Special Boat Service (SBS), the special forces unit of the Royal Navy. Purja is notable for having climbed all 14 eight-thousanders in a time of six months and six days with the aid of bottled oxygen. This was a record at the time of climbing, although it was broken in 2023 by Kristin Harila and Tenjen Sherpa, who summitted all 14 eight-thousanders in 92 days. Purja was the first person to reach the summits of Mount Everest, Lhotse and Makalu within 48 hours. In 2021, Purja, along with a team of nine other Nepalese climbers, completed the first winter ascent of K2.

The eight-thousanders are the 14 mountains recognised by the International Mountaineering and Climbing Federation (UIAA) as being more than 8,000 metres (26,247 ft) in height above sea level, and sufficiently independent of neighbouring peaks. There is no precise definition of the criteria used to assess independence, and at times, the UIAA has considered whether the list should be expanded to 20 mountain peaks by including the major satellite peaks of eight-thousanders. All of the eight-thousanders are located in the Himalayan and Karakoram mountain ranges in Asia, and their summits lie in an altitude known as the death zone.